1. Field of the Invention
The present invention relates to a digital video camera, and more particularly to a camera process circuit disposed in the digital video camera for converting output data from an image sensor into luminance data and color-difference data every data block including a plurality of data for data compression of image data using a line memory.
2. Description of the Related Art
In a standard system of color image compression, for example Joint Photographic-coding Expert Group (JPEG) or Motion Picture Image-coding Group system, output signals by a charge-coupled device (CCD) must be processed every 8.times.8 data block without the processing of raster scans when image compression is made using a standard data compression method, for example Adaptive Discrete Cosine Transform (ADCT). Conventionally, there are provided with a frame memory, and output signals from the CCD are converted into image data involving luminance data and color-difference data. These image data are stored temporally in the frame memory. Then, the image data by raster scans are read out every data block for data compression under address controls and converted every data block.
In such a conventional digital video camera which compresses the stored image data, the frame memory is an indispensable element for reading and converting the image data every data block. This increases a cost of the digital video camera.
In a case of processing motion pictures for data compression, a frame memory capacity of which is 5.9 Mbit (=768 pictures.times.480 lines.times.8 luminance signals.times.8 color-difference signals ) is necessary for storing luminance signals and color-difference signals converted from output signals of the CCD.